Name change question?

[FlyingTurk]

I have had this problem since I moved to US almost 15 years ago. In Turkey when you have First Name, Middle Name, Last Name , the middle name is the name that you go by; unlike United States.

I am thinking about changing my name to Middle Name, Last Name only. If I do this in the N-400 would this delay the process. Is it better to do this after I become a US citizen?

Thanks in advance..